The quality of medical care has been greatly enhanced by improvements to medical devices. However, the materials from which such medical devices may be made, as well as their structure and the manner in which they may be used, can produce undesirable complications. The use of medical devices such as stents, guide wires, pacing leads, catheters, or balloons in patients, for example, can result in bacterial infection, blood clotting, tissue trauma, autoimmune rejection, and other harmful side effects.
In certain situations, the likelihood or severity of these complications can be reduced by applying a coating to the medical device prior to inserting or implanting the device into a patient. Such device coatings can enhance the capabilities of medical devices. Specifically, some coatings can be used to release drugs or increase the visibility of devices to imaging systems. Other coatings may add such properties as lubricity, biocompatibility, and antimicrobial or other action to device surfaces. Still other coatings may offer a combination of these properties. An additional advantage of coatings is their ability to achieve these properties and actions without altering the bulk material properties of the medical device.
For reasons relating to cost, secondary properties of the coatings, ease of the implantation procedure, and other considerations, it may be desirable to apply a coating to only a portion or selected portions of the device. It may also be desirable to create distinct regions of the device that demonstrate properties different in function, appearance, or performance than the properties of other regions of the device. Known masking techniques in use may comprise heat shrinkable tubing or wrapping tape around the device. Such are cumbersome to apply, may damage the device during removal, and are not conducive to automation. Therefore, there is a need for selectively applying a coating to distinct regions of structures such as medical devices that can be done efficiently and provide for easy removal.